An injecting machine for receiving and mixing two different liquid resin materials (hereinafter referred to, for brevity, as “liquid materials”) together to inject a predetermined measured amount of a mixture of the two different liquid materials is known as disclosed in Japanese Patent Application Laid-open Publication (JP-A) No. 2007-76276.
FIG. 8 hereof shows a general configuration of an injecting machine disclosed in JP 2007-76276A. The disclosed injecting machine 100 includes a cylinder 101 for driving a plunger, a bracket 102 extending forwardly from a front end of the cylinder 101, an injection cylinder 103 supported by a front end of the bracket 102, a first heater 104 associated with the injection cylinder 103, a nozzle adapter 105 fixed to a front end face of the injection cylinder 103, and a nozzle 106 attached to a front end of the nozzle adapter 105. The injecting machine 100 further includes a connecting member 107 supported by the nozzle adapter 107 to extend vertically upwards, a mixing cylinder 108 connected to an upper part of the connecting member 107, a mixing shaft 109 rotatably received in the mixing cylinder 108, a sub-bracket 111 extending from the bracket 102 and supporting the mixing cylinder 108, a second heater 112 associated with the mixing cylinder 108, a drive unit 113 mounted on an upper surface of the cylinder 101 for rotating the mixing shaft 109, a mixer 104 mounted on an upper surface of a proximal end portion of the mixing cylinder 108, and first and second cylinders 115 and 116 connected to the mixer 114.
With the injecting machine 100 thus arranged, a first cylinder 115 forces a first liquid material out while the second cylinder 116 forces a second liquid material out. The first liquid material and the second liquid material are combined together in the mixer 114 to flow into the mixing cylinder 108. The first and second liquid materials are sufficiently mixed together by rotation of the mixing shaft 109 in the mixing cylinder 108 to provide a liquid mixture of the first and second liquid materials. The liquid mixture is introduced through the connecting member 107 into the injection cylinder 103.
During that time, the liquid mixture tends to solidify as the temperature goes down. To avoid this, the first heater 104 heats the injection cylinder 103, and the second heater 112 heat the mixing cylinder 108.
The mixing cylinder 108 is supported by the bracket 102 via the sub-bracket 111, while the connecting member 107 is supported by the nozzle adapter 105. With this arrangement, due to change in ambient temperature and heating by the first and second heaters 104, 112, heat expansion and contraction occurs, tending to vary the distance between the sub-bracket 111 and the connecting member 107. If the distance increases, it may occurs that the liquid mixture leaks from a mating part of the connecting member 107 and the mixing cylinder 108.
If the connecting member 107 and the mixing cylinder 108 are mechanically connected together so as to avoid leakage of the liquid mixture, the connecting member 107 or the sub-bracket will be damaged due to repeated bending force applied thereto. As for the connecting member 107 and the mixing cylinder 108, a mechanical connection cannot be employed, which will inevitably allow the occurrence of leakage of the liquid mixture from the mating part.
To meet a demand for a high material yield and a clean mixing cylinder and its surroundings, an effective leakage countermeasure is required.
An object of the present invention is to provide an injecting machine for two different liquid materials, which is configured to provide an effective leakage countermeasure.